Electrical contact couplings are usually used in rail vehicle technology to transmit data and signals, in particular control signals, as well as transmit power between two adjacent car bodies of a multi-member vehicle. The arrangement, control and size of the electrical contact couplings employed depend on the available space within the vehicle and on the number of signals to be transmitted as well as the requirements of the rail car manufacturer and/or railway operator.
Electrical contact couplings are usually rendered in such a manner that two electrical contact couplings can be coupled and uncoupled automatically. The electrical contact couplings arranged on the vehicles or car bodies to be coupled together are thereby brought together in precise alignment by means of centering devices and thereafter pressed together at sealing surfaces arranged on the front ends of the electrical contact couplings so as to achieve a reliable sealing relative to the environment. A protective flap usually covers the front end of the electrical contact coupling in the uncoupled state in order to protect the coupling elements and any live contact elements of the electrical contact coupling there may be from being contacted and from contamination.
The electrical contact coupling is usually disposed on the upper side or laterally on the coupling head of a mechanical coupling and consists of a housing having a flap and a contact support with preset contacts (male/female contacts) for transmitting electrical signals.
Reference is made in this regard to the representation provided in FIGS. 1A to 1C which depicts a known prior art electrical contact coupling 100 as an example, same shown its open state exposing the contact support 102 with male/female contacts 103.
The housing 101 of the electrical contact coupling 100 is rectangular in cross section, wherein guides 105 and frontal centering elements 106 are disposed at the outside facing the coupling head. The front face of the housing 101 of the electrical contact coupling 100 is tightly closed by the contact support 102. The contact support 102 is enclosed to the front by a profiled seal. Drill holes, in which connecting bolts are seated, are arranged in the contact support 102, whereby the male/female contacts 103 are screwed into the connecting bolts at the front side. The rear side of the housing 101 is tightly closed by a cover. The cable glands and the drive tab are located in the cover.
The flap 104 of the electrical contact coupling 100, which can protect the male/female contacts 103 on the contact support 102 as needed, is in pivotably-mounted arrangement in the front region of the housing 101 of the electrical contact coupling 100. The flap 104 protects the contacts 103 from contamination, water and mechanical damage in the uncoupled position and prevents people from accidentally making contact with them.
To couple the electrical contact couplings 100 of two adjacently disposed car bodies and/or vehicles, the electrical contact couplings 100 to be coupled are displaced forward into the common coupling plane relative to the mechanical coupling. The centering elements 106 of the facing housings 101 of the electrical contact couplings 100 slide into one another and align the housings 101 with each other. The respective contacts 103 of the electrical contact couplings 100 thereby meet one another precisely and the sealing frames are pressed against each other.
When being uncoupled, the contacts 103 of the electrical contact couplings 100 are separated again, and namely by the electrical contact couplings 100 being displaced rearward out of the coupling plane.
Each electrical contact coupling is typically provided with a corresponding mechanism so that the flap automatically opens/closes during coupling and uncoupling.
An electrical contact coupling for automatic central buffer couplings is for example known from printed publication EP 0 982 215 B1 which provides for a mechanical central buffer coupling on which the electrical contact coupling is held so as to be longitudinally displaceable. The electrical contact coupling known from this prior art comprises at least one connection line-connected plug-and-socket connection arranged at the point of coupling separation of each vehicle to be coupled. To avoid a redundant contact arrangement arranged symmetrically to the vertical central longitudinal plane of the coupling rod and to render the electrical contact coupling in a simpler and lighter design as a whole, the electrical contact coupling according to this prior art further comprises a longitudinally displaceable adapter box arranged between the respective plug-and-socket connections of the coupled rail vehicle in the coupling state and on only one of the respective plug-and-socket connections in the uncoupling state. The adapter box contains the necessary electrical connection lines for connecting the connecting lines of the vehicles/car bodies respectively to be coupled.
Furthermore, an electrical contact coupling for automatic central or central buffer couplings is known for example from printed publication DE 199 26 085 A1. This electrical contact coupling comprises a guided contact support with contacts for electrical connections mounted on the coupling head of the mechanical central or central buffer coupling and longitudinally displaceable in the longitudinal direction of the central or central buffer coupling. In order to achieve the most optimum protection possible relative the contacts for the electrical connection, this prior art provides for the contact support to be displaceable from a rearward, uncoupled position into a forward coupling-ready position, whereby the contact support is covered in the rearward position by a protective flap and exposed in the forward position with pivoted protective flap.
A fundamental problem with the electrical contact couplings known from the prior art and described above is in particular the mechanical wear on the current-carrying or data-carrying cables to be coupled by the electrical contact couplings of two adjacent car bodies. Because the electrical contact coupling in the conventional solutions first needs to be displaced relative to the mechanical coupling into the coupling-ready state, mechanical damage is unavoidable, particularly due to wear of the externally located current/data-carrying cables/cable harnesses which move relative to the coupling during the coupling process.
Moreover, a relatively complex mechanism is needed for the electrical coupling operation in the conventional solutions, same usually being mounted outside the electrical contact coupling housing. The further problem thus arises that the effects of weather such as ice and snow can lead to failure of the external components. In particular, a complete loss of the external mechanisms could result.
Regular maintenance and inspections of the current and data-carrying cables are furthermore necessary in the conventional systems in order to be able to ensure proper signal or data transmission. It is particularly necessary to regularly control and replace the connections of the electrical contact coupling parts which move relative to the mechanical coupling head since they are subjected to high mechanical wear.
A further possibility for achieving higher data transmission rates could in principle consist of providing a contactless transmission system between the car bodies of a multi-member vehicle for the transmitting of audio signals, video signals, operating data, commands and/or other bus data. To this end, the DE 10 2004 037 849 A1 printed publication for example proposes a transmission system consisting of a first HF component, a second HF component, a first transmit/receive device and a second transmit/receive device. The HF components are mounted on or in the train coupling.
However, the disadvantage to this known prior art solution is particularly to be seen in the only low-quality data transmission. In particular, a patch antenna, as printed publication DE 10 2004 37 849 A1 proposes, is only suitable to a limited extent for contactless data transmission in an automatic central buffer coupling since the signal transmission system's total attenuation is relatively high. This makes it imperative to select a correspondingly high transmission level for the respective patch antennas. Due to the disadvantageous emission pattern of patch antennas, however, a relatively high transmission level results in high interference emissions for the individual antenna elements. Thus, in practical use, such a signal transmission system may under some circumstances only provide unreliable and interference-prone data transmission.